Patent GB-768025-A (GB)
Title: Manufacture of polycyclic ketones
IPC: C07J63/00
Filed: 1953-07-17
Abstract: The invention comprises: (a) D 5(13) 2-oxo-12-methylhydrophenanthrenes which contain a hydroxy group in the 11-position or a double bond in the 1(11)-position and which are unsubstituted in the 7- and 8-positions or have fused thereto a six-membered alicylic ring having, on the carbon atom connected to the 7-position, a free or acetalized oxo group; and (b) a process for the manufacture of polycyclic ketones, wherein a D 1(9)-2-oxo-1-methyloctahydronaphthalene containing at least one hydrogen atom in the 8-position is reacted with vinyl methyl ketone and, if desired, when the product contains a tertiary hydroxy group, the elements of water are eliminated by known methods with the formation of a double bond.  Preferred starting materials, which yield the products defined at (a), are those which are unsubstituted in the 7- and 8-positions and which are also unsubstituted in the 5- and 6-positions or have fused thereto a 6-membered alicyclic ring having, on the carbon atom connected to the 6-position, a free or acetalized oxo group.  The reaction with vinyl methyl ketone may be carried out below 0 DEG  C. in the presence of a strong alkaline condensing agent, or at raised temperatures in a weakly alkaline medium (e.g. in the presence of a tertiary amine).  At raised temperatures a  : b -unsaturated ketones are directly formed, whereas the use of low temperatures (- 20 DEG  to 0 DEG  C.) gives b -hydroxyketones which may be subsequently converted to the a  : b -unsaturated ketones, e.g. with the aid of a dilute mineral acid or alkali.  The vinyl methyl ketone may be formed during the reaction, e.g. from a 4-dialkylamino- or 4-alkyleneamino-2-oxobutane (in which case the separate addition of a basic catalyst is unnecessary) or a quaternary alkyl derivative thereof (e.g. a trimethyl-g -oxobutyl-ammonium salt).  In examples: (1) D 1(9)2-oxo-1-methyloctahydronaphthalene is stirred with vinyl methyl ketone in an ethanolic solution of sodium ethoxide at - 10 DEG  to - 5 DEG  C. to produce a mixture of stereoisomeric D 5(13)-11 - hydroxy - 2 - oxo - 12 - methyldodecahydrophenanthrenes, which is refluxed with aqueous methanolic caustic soda to form a mixture of isomeric D 1(11); 5(13)-2-oxo-12-methyldecahydrophenanthrenes; alternatively one isomer is crystallized from the first mixture and dehydrated to the corresponding a  : b -unsaturated isomer; (2) the second product of (1) is obtained directly by heating the starting material under pressure with vinyl methyl ketone, triethylamine and tributylamine, or with 4-piperidino-2-oxobutane, or in a distilling vessel, with a dephlegmator, with vinyl methyl ketone and triethylamine; (3) D 8(14)-1 : 7-dioxo - 8 : 11 - dimethyldodecahydrophenanthrene is treated as in the first part of (2), and racemic D 4;9(11)-3 : 17a-dioxo-D-homoandrostadiene is isolated from the product by chromatography; (4) the starting material of (3) is stirred at - 10 DEG  to - 5 DEG  C. with vinyl methyl ketone in dioxane and a solution of sodium ethoxide in ethanol to produce (after chromatography) a mixture of stereoisomeric D 1(16) - 14 - hydroxy - 3 : 10 - dioxo - 13 : 17-dimethylhexadecahydrochrysenes, which is refluxed with aqueous methanolic caustic soda to give the product of (3) and some of its 10-epi - isomer: (5) D 8(14)-1-ethylenedioxy-7-oxo - 8 : 11 - dimethyldodecahydrophenanthrene is treated as in (4) to produce a mixture of stereoisomeric D 1(16) - 14 - hydroxy - 10-oxo - 3 - ethylenedioxy - 13 : 17 - dimethylhexadecahydrochrysenes and thence the two stereoisomeric D 1(16);9(14) - 3 - ethylenedioxy-10 - oxo - 13 : 17 - dimethyltetradecahydrochrysenes (separated by chromatrography). Specification 757,998 is referred to.